Balls have been historically used for playing a variety of games. Recently, balls have also been used for therapeutic purposes. Soft, spongy and flexible balls held in the hands have been used to exercise the hand muscles and joints used for gripping. Use of these balls do not provide therapy beyond the hands such as the arms and shoulders.
U.S. Pat. No. 5,433,438 discloses a non-bouncing ball with a rigid core surrounded by a molded layer of foamed flexible polyurethane which is bonded together during the molding process to form an integral sphere. These balls have an outer diameter of less than about 30 inches, useful for football training, physical therapy and early childhood physical education. "Medicine balls" for weight training has also been known. These balls are usually made of heavy wool shearings, kapok filler or the like, inside a stitched leather cover. These training balls are generally greater than 15 inches in diameter and can not be easily swung by one hand.
A weighted regulation size warmup ball weighing from about 2 ounces to about 12 ounces is disclosed in U.S. Pat. No. 4,943,055. To give weight to the ball, the center core is made up of metal. These balls weigh less than one pound and are considered not as effective for the therapeutic purpose of this invention.
U.S. Pat. No. 5,588,648 discloses a weighted training ball for baseball and softball batting practice. The ball is made of a solid elastomeric material having a circumference of approximately 9-16 inches, weighted between 7.5-20 ounces with a hardness rated between 40-70 A-2 Shore durometer. This weighted ball is especially adapted for use in baseball batting exercises which has the added feature of being usable in conjunction with conventional pitching machines. Although the disclosed weighted ball has some similar features or characteristics as the claimed ball, the ball does not have the required bounce to make it suitable for the purpose intended by the claimed invention. The ball disclosed, likewise, may be slightly lighter than desired. A ball weighing in the range of the claimed invention may break the bat and also cause injury to the wrist, arm and shoulder because of the recoil effect when the bat hits the ball. Recoil effect is the back vibration resulting from the resistance offered by a solid object, in this case a bat, when the ball impacts the solid object.
It is the object of this invention to provide a ball that can condition specific muscles and joints of the hands, arms and shoulders.
It is also an object of this invention to provide an exercise means that is neither cumbersome or expensive.
It is a further object of this invention to provide an exercise means that is portable, easily carried by the user.
It is further an object of this invention to provide an exercise ball of certain bounce to enable a single person to condition oneself without the need of a second person.
It is also an object of this invention to provide an exercise means adapted for use by persons or athletes of different physical size and physique.